I used the one of my friend Leo while we were in School. Some of the works we did were printed in the lunch break in the car :-) Ya know, this is a battery-powered device and with a HP-71B this printer was an unbeatable machine.
You had to use a special inkjet paper which was rather heave, but gave a nice feeling. I believe, the modern Printheads don't need this anymore, but I gave up Word processing on the 71B, when I began working with PCs (when I look at MS Word I believe I should go back to the roots :-).
BTW: the printheads are available for sale in these days (HP sells POS printers with a narrow ThinkJet system). I even remember seeing clones from Pelikan somewhere in Germany some years ago.
The obvious advantage is that you can use regular paper (ANSI A, or DIN A4 in Europe) and you don't have to copy the sheets, like you have to do with thermal paper. For dayly use with your system, I'd strongly recommend getting one, though I don't see them very often. A disadvantage is, that it misses a cut-sheet paper feeder, it was mostly designed for "endless" (is this the right word?) paper ("Endlospapier" in German) - aaah, my mind's getting better, seems it's called "fanfold" paper.
I also own a 2225A for my HPIB test equipment, but to my shame I must admit, that I've never made a Hardcopy in my home lab. Anyway, I could get it on eBay for $3.25 . Shipping to Europe was considerably more :-)